CIV E 638-SEDIMENTATION ENGINEERING
FALL 2018
MIDTERM EXAM
MONDAY, OCTOBER 22, 2018, 19:00-20:15

Name: _______________________ Red ID: ____________________ Grade:__________

Instructions: Closed book, closed notes. Use engineering paper. When you are finished, staple your work in sequence, and return this sheet with your work. Answer only ten (10) questions.

  1. Why do natural streams carry sediments? What enables sediment entrainment and transport? What are typical values of bed material sediment concentration in natural streams?

  2. Describe the fundamental criterion describing initiation of motion in natural streams. What is the typical value of Froude number that guarantees initiation of motion?

  3. List the five friction descriptors (parameters) used in hydraulic and sedimentation engineering.

  4. What is Jarrett's contribution to river mechanics? Explain.

  5. How are critical shear stress and critical velocity related?

  6. According to Humboldt, how are the destruction of forests, floods and springs related? Explain.

  7. To what did Albert Einstein attribute the cause of meandering?

  8. How does Nature minimize the changes in stage with changes in discharge? Explain.

  9. What is the difference between sediment production, sediment yield, sediment transport, and sediment routing?

  10. Explain what went wrong in 1905 during the diversion of the Colorado river in Mexico to send water to the Imperial Valley.

  11. What is the difference between the original Lane relation (1955) and the modified Lane relation? What three hydraulic relations enabled the development of the Modified Lane relation?